nouveau: codegen: Add support for OpenCL global memory buffers

Add support for OpenCL global memory buffers, note this has only
been tested with regular load and stores and likely needs more work
for e.g. atomic ops.

Tested with piglet on a gf119 and a gk107:
./piglit run -o shader -t '.*arb_shader_storage_buffer_object.*' results/shader
[9/9] pass: 9 /
./piglit run -o shader -t '.*arb_compute_shader.*' results/shader
[20/20] skip: 4, pass: 16 |

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp

@@ -1289,7 +1289,9 @@ bool Source::scanInstruction(const struct tgsi_full_instruction *inst)
          if (dst.isIndirect(0))
             indirectTempArrays.insert(dst.getArrayId());
       } else
-      if (dst.getFile() == TGSI_FILE_BUFFER) {
+      if (dst.getFile() == TGSI_FILE_BUFFER ||
+          (dst.getFile() == TGSI_FILE_MEMORY &&
+           memoryFiles[dst.getIndex(0)].mem_type == TGSI_MEMORY_TYPE_GLOBAL)) {
          info->io.globalAccess |= 0x2;
       }
    }
@@ -1300,7 +1302,9 @@ bool Source::scanInstruction(const struct tgsi_full_instruction *inst)
          if (src.isIndirect(0))
             indirectTempArrays.insert(src.getArrayId());
       } else
-      if (src.getFile() == TGSI_FILE_BUFFER) {
+      if (src.getFile() == TGSI_FILE_BUFFER ||
+          (src.getFile() == TGSI_FILE_MEMORY &&
+           memoryFiles[src.getIndex(0)].mem_type == TGSI_MEMORY_TYPE_GLOBAL)) {
          info->io.globalAccess |= (insn.getOpcode() == TGSI_OPCODE_LOAD) ?
                0x1 : 0x2;
       } else
@@ -1534,6 +1538,10 @@ Converter::makeSym(uint tgsiFile, int fileIdx, int idx, int c, uint32_t address)
 
    if (tgsiFile == TGSI_FILE_MEMORY) {
       switch (code->memoryFiles[fileIdx].mem_type) {
+      case TGSI_MEMORY_TYPE_GLOBAL:
+         /* No-op this is the default for TGSI_FILE_MEMORY */
+         sym->setFile(FILE_MEMORY_GLOBAL);
+         break;
       case TGSI_MEMORY_TYPE_SHARED:
          sym->setFile(FILE_MEMORY_SHARED);
          break;